There is a widely used game system that allows three or more players to play one game via a network. A type of this game system advances a game as a unit for a group including a server, or alternatively, one game terminal is selected as a parent node (a server or a master node) and game terminals are selected as child nodes (clients or slave nodes). The number of child nodes is variable for each group within a range that has an upper limit and a lower limit, i.e., the number of child nodes can differ among different groups.
In such a game system, a communication group including plural game terminals is usually provided in each venue, and a group of game terminals (a player group) that will be used by players is formed across plural venues. Communication between game terminals is performed via a communication path allocated to each communication group (venue). A communication path is shared by game terminals belonging to a communication group that corresponds to the communication path. In this game system, a certain amount of the bandwidth corresponding to the upper limit of the range will be secured for a parent node if the remainder of the bandwidth in a communication path is sufficient while a game is proceeding.
Japanese Patent Application Laid-Open Publication No. 2005-137812 proposes a technique in which, in a game system having a fixed number of child nodes, communication failures can be minimized even in a case in which the bandwidth of each communication path is smaller than the maximum amount of bandwidth required for each communication path. Also, in this technique, while a game is being played, a certain amount of the bandwidth will be continuously secured if the remaining amount of bandwidth of a communication path is sufficient.
However, the amount of bandwidth required for a parent node while a game is being played depends on the number of child nodes in a game system in which the number of child nodes is variable. Therefore, in the conventional technique, a bandwidth in an amount that is greater than the bandwidth required by a parent node is sometimes continuously secured. In other words, in the conventional technique, extra bandwidth that will never be used is sometimes continuously secured for a parent node for a long period of time. This is one of the factors that degrade the use efficiency of the bandwidth.